<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>体验rem</title>
    <script src="js/flexible.js"></script>
    <style>
        div {
            /* 
                rem单位：相对单位
                1rem = 1html字号大小
            */
            width: 5rem;
            height: 3rem;
            background-color: pink;
        }
    </style>
</head>
<body>
    <div></div>
</body>
</html>
